William sawtee



W. SAWYER. Electric Lamp.

No. 227,387. Patented M ay 11, 1880..

WITNESSES. W 01.26.

' ".PETERS, PHOYO-UTIIOGRAPHER, WASHIN UNITED STATES PATENT OFFICE.

WILLIAM SAWYER, OF NEW YORK, Y. ASSIGNOR TO THE EASTERN ELEG- TRIOMANUFACTURING COMPANY, OF MIDDLETOWN, CONN.

ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 227,387, dated May 11,1880.

Application filed January 14,1880.

To all whom. it may concern:

Be it known that 1, WILLIAM SAWYER, a citizen of the United States,residing at New York, in the county of New York and State of New York,have invented certain new and usetul Improvements in Electric Lamps, ofwhich the following is a full, clear, and exact description.

My invention relates to that method of electric lighting in which apencil of carbon hermetically sealed in a glass globe charged withnitrogen gas is rendered incandescent by the passage of the electriccurrent, and has special reference to the hermetical sealing of theopening through which the globe is filled with the nitrogen gas.

The general method of making the lamp airtight is fully set forth inother applications filed by me, and I have therefore not included thesame in the present specification, except in so far as I seal theaperture employed in filling the lamp with nitrogen. Through thisaperture a metal plug, B, in the accompanying drawing, is pushed asideby a tube, through which nitrogen is forced into the lamp. The nitrogenentering this tube displaces the air, and when, finally, the lamp ischarged to a sufficient degree of purity, I withdraw the tube, stillpermitting the nitrogen to flow until, finally, the tube shall havepassed below the interior upper surface of the cup A and the plug B isdrawn down by means of the wire G. I next invert the lamp and pourmelted sealing-wax around the plug B. Then I place upon the bottom ofthe cup A one or more soft-rubber washers, D, and, by means of screws E,I set down upon the lower cap, 0, until this particular joint isair-tight. Finally, through the openin g W, in which there is cut athread suited to an ordiu ary gas-bracket, I pour melted bees-wax F,when the lamp is complete for use.

Having thus fully described my invention, what I claim as such, anddesire to secure by Letters Patent, is-

The combination of the plug B and wire G with the cap 0, having anopening, W, and the liquefiable filling material F, for the purpose ofsealing the filling-joint of an electric lamp, substantially as setforth.

WM. SAWYER. Witnesses:

' E. R. KNoWLEs, 'F. L. ROWLAND.

